Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.
2 min synopsisUK scopeSources checked 27 Aug 2026Clinical review pending
!
Unexpected invasive or postoperative complication
DCIS itself rarely creates an acute emergency, but a rapidly expanding postoperative haematoma, infection or final pathology showing invasive cancer with untreated axillary risk requires prompt reassessment.
Action: Use surgical ABCDE and haemorrhage or sepsis care when acutely unwell, contact the breast team urgently and return unexpected microinvasion or invasion to the MDT for receptor testing, nodal-staging feasibility and additional local or systemic treatment rather than assuming the DCIS plan remains complete.
Synopsis
Diagnose screen-detected and symptomatic ductal carcinoma in situ accurately, exclude occult invasion, tailor breast and axillary surgery, use radiotherapy and endocrine risk reduction appropriately and avoid metastatic overtreatment.
DCIS consists of malignant epithelial cells confined within breast ducts by an intact myoepithelial layer and basement membrane; pure DCIS cannot metastasise.
Most cases are detected as mammographic microcalcification rather than a palpable lump, but a mass or nipple discharge increases concern for more extensive disease or occult invasion.
Stereotactic or tomosynthesis-guided vacuum-assisted sampling is preferred for many calcification-only lesions because it obtains representative tissue and confirms that target calcification was removed.
Key red flags
A palpable mass, architectural distortion, suspicious node or extensive high-grade calcification increases the probability that biopsy has under-sampled invasive cancer.
Unexpected invasive disease
Microinvasion or stromal invasion on excision changes nodal, receptor, systemic and sometimes margin decisions and requires prompt MDT restaging.
Investigation priorities
01
First-line diagnostic mammography with magnificationFirst stepFirst line
Characterise morphology and distribution of calcification and estimate the full field requiring biopsy and excision.
Sample calcification widely enough to diagnose grade and assess for invasive or atypical components.
Management branches
CalcificationSample the complete radiological target
Screening or symptomatic mammography identifies suspicious calcification without proven invasion.
Obtain diagnostic magnification views, map number and span of groups and add ultrasound when a mass, duct or node is present.
Perform stereotactic or tomosynthesis-guided vacuum-assisted biopsy, confirm target calcification in the cores and place a marker for later localisation.
Key medicines
Tamoxifen after ER-positive DCISGive tamoxifen 20 mg orally once daily, commonly for 5 years, when endocrine risk reduction is chosen after breast-conserving treatment; duration follows the individual breast-oncology plan.
Anastrozole after menopauseGive anastrozole 1 mg orally once daily for the planned preventive course in an appropriate postmenopausal patient when selected instead of tamoxifen.
National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.